At present, the space available under the engine bonnet of vehicles is ever more restricted, particularly around the engine block, and tends to favour integration of the functions to be carried out with a view to reducing size, while maintaining their quality and performance longevity, on which the vehicle's operational reliability depends.
In addition, in terms of developing and manufacturing internal combustion engine vehicles, the current trend is no longer to think in terms of isolated elements, namely components or parts, but in terms of assemblies, units or modules, each fulfilling an overall function or several interdependent functions.
This is particularly the case for functions connected simultaneously to the engine cooling circuit and the recirculation or reinjection of exhaust gases (EGR).
It would of course be advantageous, for reasons of compactness and size reduction, as well as for reasons of reducing the number of parts and assembly and fitting operations, to integrate, for example, at least some of the functions of regulation and distribution of the coolant liquid when it leaves the engine block with the cooling function of the gases to be recycled, to achieve a single structural unit fulfilling these various functions.
In addition, if such a unit could also incorporate conduit portions of the respective circulation circuits, it would be possible to reduce still further the number of separate parts needed, as well as the length of the corresponding circuits, allowing, for example, rapid warming of the engine to be achieved after a cold start.
Moreover, to achieve a compact installation that does not require a particular support structure to retain it under the vehicle's bonnet, it would be useful to fix such a unit directly on the engine block.
Finally, it is also advantageous, for economic reasons, to produce at least certain constituent parts of such a unit in a plastics material, which must however be protected against too high temperatures.